197149661 has 2 divisors, whose sum is σ = 197149662. Its totient is φ = 197149660.

The previous prime is 197149657. The next prime is 197149691. The reversal of 197149661 is 166941791.

It is a happy number.

197149661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 170172025 + 26977636 = 13045^2 + 5194^2 .

It is a cyclic number.

It is not a de Polignac number, because 197149661 - 2² = 197149657 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197149691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98574830 + 98574831.

It is an arithmetic number, because the mean of its divisors is an integer number (98574831).

Almost surely, 2^197149661 is an apocalyptic number.

It is an amenable number.

197149661 is a deficient number, since it is larger than the sum of its proper divisors (1).

197149661 is an equidigital number, since it uses as much as digits as its factorization.

197149661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 44.

The square root of 197149661 is about 14040.9992878000. Note that the first 3 decimals coincide. The cubic root of 197149661 is about 582.0120971100.

The spelling of 197149661 in words is "one hundred ninety-seven million, one hundred forty-nine thousand, six hundred sixty-one".